This term is true for Bitcoin as well. Both can be exchangeable with essential goods and they are acceptable in our society.
Do you know a lot of stores that sell eggs or flour for gold or Bitcoin?
Gold is valuable because it's rare and has a limited supply.
If you think that it's enough to qualify as digital gold, then Pokemon trading cards are also digital gold. Or World of Warcraft's currency.
People call Bitcoin digital gold, because they want to make an argument that it's a hedge against inflation. The problem is, Bitcoin is not showing any good correlation with inflation or other macroeconomic indicators, it's completely unpredictable. The main point of a hedge is to act predictably under some circumstances, and Bitcoin still can't do that.
I agree mainly with your arguments. One of the attributes I like with bitcoin over gold is the known total and circulating supply. We can never really understand golds max supply as well as circulating supply. The details are more comfortable with me knowing the parameters of all aspects with supply. Although there are "forever lost" or burned coins, we still know the top end of those supply numbers.
And yes I can certainly use bitcoin at various places, alot more than I can gold.